…The quality of the test determines its entire value: a poorly performed manoeuvre gives a falsely low FVC and thus a falsely normal FEV₁/FVC…

…pattern: FEV₁/FVC below the lower limit of normal (traditionally < 0.70). A restrictive pattern: a reduced TLC — this cannot be established with spirometry…

…alternative etiologies are excluded by diagnostic testing or failed therapeutic trials. If alternative causes of cough are suspected, specific diagnostic pathways may be pursued. Spirometry